/**
 * Created by joustany on 17/12/13.
 */
/*!
 jQuery Waypoints - v1.1.2
 Copyright (c) 2011 Caleb Troughton
 Dual licensed under the MIT license and GPL license.
 https://github.com/imakewebthings/jquery-waypoints/blob/master/MIT-license.txt
 https://github.com/imakewebthings/jquery-waypoints/blob/master/GPL-license.txt
 */

/*
 Waypoints is a small jQuery plugin that makes it easy to execute a function
 whenever you scroll to an element.

 GitHub Repository: https://github.com/imakewebthings/jquery-waypoints
 Documentation and Examples: http://imakewebthings.github.com/jquery-waypoints

 Changelog:
 v1.1.2
 - Fixed error thrown by waypoints with triggerOnce option that were
 triggered via resize refresh.
 v1.1.1
 - Fixed bug in initialization where all offsets were being calculated
 as if set to 0 initially, causing unwarranted triggers during the
 subsequent refresh.
 - Added onlyOnScroll, an option for individual waypoints that disables
 triggers due to an offset refresh that crosses the current scroll
 point. (All credit to @knuton on this one.)
 v1.1
 - Moved the continuous option out of global settings and into the options
 object for individual waypoints.
 - Added the context option, which allows for using waypoints within any
 scrollable element, not just the window.
 v1.0.2
 - Moved scroll and resize handler bindings out of load.  Should play nicer
 with async loaders like Head JS and LABjs.
 - Fixed a 1px off error when using certain % offsets.
 - Added unit tests.
 v1.0.1
 - Added $.waypoints('viewportHeight').
 - Fixed iOS bug (using the new viewportHeight method).
 - Added offset function alias: 'bottom-in-view'.
 v1.0
 - Initial release.

 Support:
 - jQuery versions 1.4.3+
 - IE6+, FF3+, Chrome 6+, Safari 4+, Opera 11
 - Other versions and browsers may work, these are just the ones I've looked at.
 */

(function($, wp, wps, window, undefined){
    '$:nomunge';

    var $w = $(window),

        // Keeping common strings as variables = better minification
        eventName = 'waypoint.reached',

        /*
         For the waypoint and direction passed in, trigger the waypoint.reached
         event and deal with the triggerOnce option.
         */
        triggerWaypoint = function(way, dir) {
            way.element.trigger(eventName, dir);
            if (way.options.triggerOnce) {
                way.element[wp]('destroy');
            }
        },

        /*
         Given a jQuery element and Context, returns the index of that element in the waypoints
         array.  Returns the index, or -1 if the element is not a waypoint.
         */
        waypointIndex = function(el, context) {
            var i = context.waypoints.length - 1;
            while (i >= 0 && context.waypoints[i].element[0] !== el[0]) {
                i -= 1;
            }
            return i;
        },

        // Private list of all elements used as scrolling contexts for waypoints.
        contexts = [],

        /*
         Context Class - represents a scrolling context.  Properties include:
         element: jQuery object containing a single HTML element.
         waypoints: Array of waypoints operating under this scroll context.
         oldScroll: Keeps the previous scroll position to determine scroll direction.
         didScroll: Flag used in scrolling the context's scroll event.
         didResize: Flag used in scrolling the context's resize event.
         doScroll: Function that checks for crossed waypoints. Called from throttler.
         */
        Context = function(context) {
            $.extend(this, {
                'element': $(context),

                /*
                 Starting at a ridiculous negative number allows for a 'down' trigger of 0 or
                 negative offset waypoints on load. Useful for setting initial states.
                 */
                'oldScroll': -99999,

                /*
                 List of all elements that have been registered as waypoints.
                 Each object in the array contains:
                 element: jQuery object containing a single HTML element.
                 offset: The window scroll offset, in px, that triggers the waypoint event.
                 options: Options object that was passed to the waypoint fn function.
                 */
                'waypoints': [],

                didScroll: false,
                didResize: false,

                doScroll: $.proxy(function() {
                    var newScroll = this.element.scrollTop(),

                        // Are we scrolling up or down? Used for direction argument in callback.
                        isDown = newScroll > this.oldScroll,
                        that = this,

                        // Get a list of all waypoints that were crossed since last scroll move.
                        pointsHit = $.grep(this.waypoints, function(el, i) {
                            return isDown ?
                                (el.offset > that.oldScroll && el.offset <= newScroll) :
                                (el.offset <= that.oldScroll && el.offset > newScroll);
                        }),
                        len = pointsHit.length;

                    // iOS adjustment
                    if (!this.oldScroll || !newScroll) {
                        $[wps]('refresh');
                    }

                    // Done with scroll comparisons, store new scroll before ejection
                    this.oldScroll = newScroll;

                    // No waypoints crossed? Eject.
                    if (!len) return;

                    // If several waypoints triggered, need to do so in reverse order going up
                    if (!isDown) pointsHit.reverse();

                    /*
                     One scroll move may cross several waypoints.  If the waypoint's continuous
                     option is true it should fire even if it isn't the last waypoint.  If false,
                     it will only fire if it's the last one.
                     */
                    $.each(pointsHit, function(i, point) {
                        if (point.options.continuous || i === len - 1) {
                            triggerWaypoint(point, [isDown ? 'down' : 'up']);
                        }
                    });
                }, this)
            });

            // Setup scroll and resize handlers.  Throttled at the settings-defined rate limits.
            $(context).scroll($.proxy(function() {
                if (!this.didScroll) {
                    this.didScroll = true;
                    window.setTimeout($.proxy(function() {
                        this.doScroll();
                        this.didScroll = false;
                    }, this), $[wps].settings.scrollThrottle);
                }
            }, this)).resize($.proxy(function() {
                if (!this.didResize) {
                    this.didResize = true;
                    window.setTimeout($.proxy(function() {
                        $[wps]('refresh');
                        this.didResize = false;
                    }, this), $[wps].settings.resizeThrottle);
                }
            }, this));

            $w.load($.proxy(function() {
                /*
                 Fire a scroll check, should the page be loaded at a non-zero scroll value,
                 as with a fragment id link or a page refresh.
                 */
                this.doScroll();
            }, this));
        },

        /* Returns a Context object from the contexts array, given the raw HTML element
         for that context. */
        getContextByElement = function(element) {
            var found = null;

            $.each(contexts, function(i, c) {
                if (c.element[0] === element) {
                    found = c;
                    return false;
                }
            });

            return found;
        },

        // Methods exposed to the effin' object
        methods = {
            /*
             jQuery.fn.waypoint([handler], [options])

             handler
             function, optional
             A callback function called when the user scrolls past the element.
             The function signature is function(event, direction) where event is
             a standard jQuery Event Object and direction is a string, either 'down'
             or 'up' indicating which direction the user is scrolling.

             options
             object, optional
             A map of options to apply to this set of waypoints, including where on
             the browser window the waypoint is triggered. For a full list of
             options and their defaults, see $.fn.waypoint.defaults.

             This is how you register an element as a waypoint. When the user scrolls past
             that element it triggers waypoint.reached, a custom event. Since the
             parameters for creating a waypoint are optional, we have a few different
             possible signatures. Let鈥檚 look at each of them.

             someElements.waypoint();

             Calling .waypoint with no parameters will register the elements as waypoints
             using the default options. The elements will fire the waypoint.reached event,
             but calling it in this way does not bind any handler to the event. You can
             bind to the event yourself, as with any other event, like so:

             someElements.bind('waypoint.reached', function(event, direction) {
             // make it rain
             });

             You will usually want to create a waypoint and immediately bind a function to
             waypoint.reached, and can do so by passing a handler as the first argument to
             .waypoint:

             someElements.waypoint(function(event, direction) {
             if (direction === 'down') {
             // do this on the way down
             }
             else {
             // do this on the way back up through the waypoint
             }
             });

             This will still use the default options, which will trigger the waypoint when
             the top of the element hits the top of the window. We can pass .waypoint an
             options object to customize things:

             someElements.waypoint(function(event, direction) {
             // do something amazing
             }, {
             offset: '50%'  // middle of the page
             });

             You can also pass just an options object.

             someElements.waypoint({
             offset: 100  // 100px from the top
             });

             This behaves like .waypoint(), in that it registers the elements as waypoints
             but binds no event handlers.

             Calling .waypoint on an existing waypoint will extend the previous options.
             If the call includes a handler, it will be bound to waypoint.reached without
             unbinding any other handlers.
             */
            init: function(f, options) {
                // Register each element as a waypoint, add to array.
                this.each(function() {
                    var cElement = $.fn[wp].defaults.context,
                        context,
                        $this = $(this);

                    // Default window context or a specific element?
                    if (options && options.context) {
                        cElement = options.context;
                    }

                    // Find the closest element that matches the context
                    if (!$.isWindow(cElement)) {
                        cElement = $this.closest(cElement)[0];
                    }
                    context = getContextByElement(cElement);

                    // Not a context yet? Create and push.
                    if (!context) {
                        context = new Context(cElement);
                        contexts.push(context);
                    }

                    // Extend default and preexisting options
                    var ndx = waypointIndex($this, context),
                        base = ndx < 0 ? $.fn[wp].defaults : context.waypoints[ndx].options,
                        opts = $.extend({}, base, options);

                    // Offset aliases
                    opts.offset = opts.offset === "bottom-in-view" ?
                        function() {
                            var cHeight = $.isWindow(cElement) ? $[wps]('viewportHeight')
                                : $(cElement).height();
                            return cHeight - $(this).outerHeight();
                        } : opts.offset;

                    // Update, or create new waypoint
                    if (ndx < 0) {
                        context.waypoints.push({
                            'element': $this,
                            'offset': null,
                            'options': opts
                        });
                    }
                    else {
                        context.waypoints[ndx].options = opts;
                    }

                    // Bind the function if it was passed in.
                    if (f) {
                        $this.bind(eventName, f);
                    }
                });

                // Need to re-sort+refresh the waypoints array after new elements are added.
                $[wps]('refresh');

                return this;
            },


            /*
             jQuery.fn.waypoint('remove')

             Passing the string 'remove' to .waypoint unregisters the elements as waypoints
             and wipes any custom options, but leaves the waypoint.reached events bound.
             Calling .waypoint again in the future would reregister the waypoint and the old
             handlers would continue to work.
             */
            remove: function() {
                return this.each(function(i, el) {
                    var $el = $(el);

                    $.each(contexts, function(i, c) {
                        var ndx = waypointIndex($el, c);

                        if (ndx >= 0) {
                            c.waypoints.splice(ndx, 1);
                        }
                    });
                });
            },

            /*
             jQuery.fn.waypoint('destroy')

             Passing the string 'destroy' to .waypoint will unbind all waypoint.reached
             event handlers on those elements and unregisters them as waypoints.
             */
            destroy: function() {
                return this.unbind(eventName)[wp]('remove');
            }
        },

        /*
         Methods used by the jQuery object extension.
         */
        jQMethods = {

            /*
             jQuery.waypoints('refresh')

             This will force a recalculation of each waypoint鈥檚 trigger point based on
             its offset option and context. This is called automatically whenever the window
             (or other defined context) is resized, new waypoints are added, or a waypoint鈥檚
             options are modified. If your project is changing the DOM or page layout without
             doing one of these things, you may want to manually call this refresh.
             */
            refresh: function() {
                $.each(contexts, function(i, c) {
                    var isWin = $.isWindow(c.element[0]),
                        contextOffset = isWin ? 0 : c.element.offset().top,
                        contextHeight = isWin ? $[wps]('viewportHeight') : c.element.height(),
                        contextScroll = isWin ? 0 : c.element.scrollTop();

                    $.each(c.waypoints, function(j, o) {
                        /* $.each isn't safe from element removal due to triggerOnce.
                         Should rewrite the loop but this is way easier. */
                        if (!o) return;

                        // Adjustment is just the offset if it's a px value
                        var adjustment = o.options.offset,
                            oldOffset = o.offset;

                        // Set adjustment to the return value if offset is a function.
                        if (typeof o.options.offset === "function") {
                            adjustment = o.options.offset.apply(o.element);
                        }
                        // Calculate the adjustment if offset is a percentage.
                        else if (typeof o.options.offset === "string") {
                            var amount = parseFloat(o.options.offset);
                            adjustment = o.options.offset.indexOf("%") ?
                                Math.ceil(contextHeight * (amount / 100)) : amount;
                        }

                        /*
                         Set the element offset to the window scroll offset, less
                         all our adjustments.
                         */
                        o.offset = o.element.offset().top - contextOffset
                            + contextScroll - adjustment;

                        /*
                         An element offset change across the current scroll point triggers
                         the event, just as if we scrolled past it unless prevented by an
                         optional flag.
                         */
                        if (o.options.onlyOnScroll) return;

                        if (oldOffset !== null && c.oldScroll > oldOffset && c.oldScroll <= o.offset) {
                            triggerWaypoint(o, ['up']);
                        }
                        else if (oldOffset !== null && c.oldScroll < oldOffset && c.oldScroll >= o.offset) {
                            triggerWaypoint(o, ['down']);
                        }
                    });

                    // Keep waypoints sorted by offset value.
                    c.waypoints.sort(function(a, b) {
                        return a.offset - b.offset;
                    });
                });
            },


            /*
             jQuery.waypoints('viewportHeight')

             This will return the height of the viewport, adjusting for inconsistencies
             that come with calling $(window).height() in iOS. Recommended for use
             within any offset functions.
             */
            viewportHeight: function() {
                return (window.innerHeight ? window.innerHeight : $w.height());
            },


            /*
             jQuery.waypoints()

             This will return a jQuery object with a collection of all registered waypoint
             elements.

             $('.post').waypoint();
             $('.ad-unit').waypoint(function(event, direction) {
             // Passed an ad unit
             });
             console.log($.waypoints());

             The example above would log a jQuery object containing all .post and .ad-unit
             elements.
             */
            aggregate: function() {
                var points = $();
                $.each(contexts, function(i, c) {
                    $.each(c.waypoints, function(i, e) {
                        points = points.add(e.element);
                    });
                });
                return points;
            }
        };


    /*
     fn extension.  Delegates to appropriate method.
     */
    $.fn[wp] = function(method) {

        if (methods[method]) {
            return methods[method].apply(this, Array.prototype.slice.call(arguments, 1));
        }
        else if (typeof method === "function" || !method) {
            return methods.init.apply(this, arguments);
        }
        else if (typeof method === "object") {
            return methods.init.apply(this, [null, method]);
        }
        else {
            $.error( 'Method ' +  method + ' does not exist on jQuery ' + wp );
        }
    };


    /*
     The default options object that is extended when calling .waypoint. It has the
     following properties:

     context
     string | element | jQuery*
     default: window
     The context defines which scrollable element the waypoint belongs to and acts
     within. The default, window, means the waypoint offset is calculated with relation
     to the whole viewport.  You can set this to another element to use the waypoints
     within that element.  Accepts a selector string, *but if you use jQuery 1.6+ it
     also accepts a raw HTML element or jQuery object.

     continuous
     boolean
     default: true
     If true, and multiple waypoints are triggered in one scroll, this waypoint will
     trigger even if it is not the last waypoint reached.  If false, it will only
     trigger if it is the last waypoint.

     offset
     number | string | function
     default: 0
     Determines how far the top of the element must be from the top of the browser
     window to trigger a waypoint. It can be a number, which is taken as a number
     of pixels, a string representing a percentage of the viewport height, or a
     function that will return a number of pixels.

     onlyOnScroll
     boolean
     default: false
     If true, this waypoint will not trigger if an offset change during a refresh
     causes it to pass the current scroll point.

     triggerOnce
     boolean
     default: false
     If true, the waypoint will be destroyed when triggered.

     An offset of 250 would trigger the waypoint when the top of the element is 250px
     from the top of the viewport. Negative values for any offset work as you might
     expect. A value of -100 would trigger the waypoint when the element is 100px above
     the top of the window.

     offset: '100%'

     A string percentage will determine the pixel offset based on the height of the
     window. When resizing the window, this offset will automatically be recalculated
     without needing to call $.waypoints('refresh').

     // The bottom of the element is in view
     offset: function() {
     return $.waypoints('viewportHeight') - $(this).outerHeight();
     }

     Offset can take a function, which must return a number of pixels from the top of
     the window. The this value will always refer to the raw HTML element of the
     waypoint. As with % values, functions are recalculated automatically when the
     window resizes. For more on recalculating offsets, see $.waypoints('refresh').

     An offset value of 'bottom-in-view' will act as an alias for the function in the
     example above, as this is a common usage.

     offset: 'bottom-in-view'

     You can see this alias in use on the Scroll Analytics example page.

     The triggerOnce flag, if true, will destroy the waypoint after the first trigger.
     This is just a shortcut for calling .waypoint('destroy') within the waypoint
     handler. This is useful in situations such as scroll analytics, where you only
     want to record an event once for each page visit.

     The context option lets you use Waypoints within an element other than the window.
     You can define the context with a selector string and the waypoint will act within
     the nearest ancestor that matches this selector.

     $('.something-scrollable .waypoint').waypoint({
     context: '.something-scrollable'
     });

     You can see this in action on the Dial Controls example.
     */
    $.fn[wp].defaults = {
        continuous: true,
        offset: 0,
        triggerOnce: false,
        context: window
    };





    /*
     jQuery object extension. Delegates to appropriate methods above.
     */
    $[wps] = function(method) {
        if (jQMethods[method]) {
            return jQMethods[method].apply(this);
        }
        else {
            return jQMethods['aggregate']();
        }
    };


    /*
     $.waypoints.settings

     Settings object that determines some of the plugin鈥檚 behavior.

     resizeThrottle
     number
     default: 200
     For performance reasons, the refresh performed during resizes is
     throttled. This value is the rate-limit in milliseconds between resize
     refreshes. For more information on throttling, check out Ben Alman鈥檚
     throttle / debounce plugin.
     http://benalman.com/projects/jquery-throttle-debounce-plugin/

     scrollThrottle
     number
     default: 100
     For performance reasons, checking for any crossed waypoints during a
     scroll event is throttled. This value is the rate-limit in milliseconds
     between scroll checks. For more information on throttling, check out Ben
     Alman鈥檚 throttle / debounce plugin.
     http://benalman.com/projects/jquery-throttle-debounce-plugin/
     */
    $[wps].settings = {
        resizeThrottle: 200,
        scrollThrottle: 100
    };

    $w.load(function() {
        // Calculate everything once on load.
        $[wps]('refresh');
    });
})(jQuery, 'waypoint', 'waypoints', this);
